Grinding-machine feeding mechanism.



c. M. GONRADSON. GRINDING 1l[l^.GHIIUJl FEEDING MEOHANISM. APPLICATIONFILED NOV.18,

c. GONRADSON. GBINDIG MACHINE FEEDING MEGHANISM.

APPLICATION FILED NOV. 18, 1907.

Patented May 17, 1910.

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l c. M. ooNRADsoN. GRINDING MACHINE FEEDING MEGHANISM.

APPLIOATIONTILED NOV. 18, 1907.

Patented. May 17, 1910.

INVENTI? G.M. GONRADSON.

GRINDING MACHINE FEBDING MBGHANISM.

APPLIUATION- FILED NOV. 19, 1907.

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Patented May 17, 1910.

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CONRAD lVI. CONRADSON, 0F MADISON, WISCONSIN, ASSIGNOR T0 VERNETTE E.PRENTICE, OF NEW' YORK, N. Y.

GRINDING-MACHINE FEEDING- MECHANISM.

To all 'whom it may concern:

Be it known that I, CONRAD M. CONRAD- soN, a citizen of the UnitedStates, residing at Madison, in the county of Dane and State ofl/Visconsin, have invented a new and useful Grinding-Machine FeedingMechanism, of which the following is a specification.

My invention relates to machines for grinding plane or cylindricalsurfaces with a rotating einery or other abrasive tool.

One object of my invention is to obtain a more precise control of theabrasive tool relative to the work, in order to produce the workaccurately and economically.

Another object is to have the feed operating mechanism convenient, andso that the abrasive wheel can be moved either to or from the workprecisely.

Still another object is to provide means adapted to make the feedoptionally variable or constant and also to have the machineautomatically stop grinding when a predetermined size of work isreached.

I believe that I am the first to apply a variable feed to a grindingmachine. On one well known make of grinding lathe there are two feeds soarranged that the operator can use a coarse feed at first for roughlygrinding the work to approximately the required size, and then use afine feed for finishing it to the exact size. But my new feedingmechanism for grinding machines can feed intermittently by a constant orvarying increment,depending upon the predetermined shape of the camface, and when the work is about the required size it can stop feedingand allow the work to make a predetermined number of passes before themachine autoinatically stops, or is stopped by hand. This ability tovary the feed and to use a cani of just the proper shape for the work inhand, is a valuable improvement, as for instance if the work is acasting or forging on which the surface to be ground has not previouslybeen machined, as by a lathe, or a planer, then the surface willprobably have uneven parts and small projections. Or if the work haspreviously been roughly machined leaving the tool marks, in either case,my new grinding machine feeding mechanism can be made to feed by largeincrements at first removing the high spots on the work, and then bygradually decreasing increments as the work approaches the finisheddimensions and thus accomplish the same or better results Specificationof Letters Patent.

Application filed November 18, 1907.

Patented May 1"?, 1910.

Serial No. 402,771.

in about one half of the time required by the old and non-sensitiveconstant increment feeding mechanisms now in use. I obtain these andother results by the use of a cam mechanism and a knife edge mechanism,both of the said mechanisms are shown but the knife edge mechanism onlyis claimed in this application. The cam mechanism is claimed in another'application, Serial Number 402,770 filed November 18 1907.

The invention consists in the construction and combination of parts tobe more fully described hereinafter and particularly set forth in theclaims.

Referring to the accompanying drawings forming a part of thisspecification, in which similar characters of reference indicatecorresponding parts in all the views, Figure 1 is a partial plan View ofmy grinding machine feeding mechanism shown partly in section. Fig. 2 isa partial front view of the same with the hand wheels and cam removed.Fig. 3 is a plan view shown partly in section of the mechanism foractuating the feed through a connecting rod, by means of a reciprocatingtable. Fig. 4 is a broken front view of the feeding mechanism showingthe hand wheel and ratchet wheel. Fig. 5 is a front view of themechanism for actuating the ratchet wheel through a connecting rod. Fig.6 is a broken sectional view of the reciprocating table showing theadjustable dogs for operating the ratchet connecting rod throu hintermediate mechanism. Fig. 7 is a 'ront elevation of a grindingmachine for cylindrical work equipped with my new feeding mechanism.Fig. 8 is a side View of the same with a part of the feeding mechanismremoved. Fig. 9 is a top View of the same with a part of the feedingmechanism removed. Fig. 10 is a partial rear view showing the grindingwheel slide counterweight mechanism. Fig. 11 is a development of thefeed cam; Fig. 12 is an elevation and Fig. 13 a plan of thefeed-adjusting crank; Fig.

14 is a plan and Fig. 15 an elevation of the feed trip lever; Fig. 16 isa plan and Fig.

17' an elevation of the reverse clutch trip lever; Fig. 18 is a plan andFig. 19 an elevation of a bracket supporting the feed works; Fig. 20 isa plan and Fig. 21 an elevation of the feed-adjusting yoke; Fig. 22

end elevation and Fig. 25 a plan of the feedadjusting slide; Fig. 26 isa plan and Fig. 27 an elevation of a knife-edge fulcrum for the feedlever; Fig. 28 is a plan and Fig. 29 an elevation of the feed leverfulcrum abutment.

In Figs. 7, 8, 9, and 10, 1 is the main base of the machine, 2 is thewheel base securely bolted to the main base, 3 is the table adapted toreciprocate in the tracks 3 4 is the swivel rigidly clamped to the table3 and upon which are mounted with longitudinal adjustment, the headstock5 and tailstock 6, the headstock having means to rotate the work 55 oncenters 5 and 6, 7 is the wheel slide mounted to slide at right anglesto the table in the tracks 7 in the wheel base 2, on this slide isrotatively mounted a spindle 8, Fig. 10 having its axis preferablyparallel to the track 3; fastened to the spindle 8, is an abrasive wheel9, of emery or other material. Also fastened to the spindle 8 is apulley 10. Fastened to the wheel slide 7 is a. half nut 11 engaging thethreaded portion of screw 12, the latter being journaled in the base 1and wheel base 2, Fig. 3 and also ada ted to slide longitudinallytherein. Pivote on the bushings 13 and 14 and located inside of thewheel base 2 is a bell crank 16 in which are mounted two rotatable idlerpulleys 17 and 18 respectively on studs 19 and 20.

The bushings 13 and 14 are fastened in the wheel base 2 and haveournaled in them the driving shaft 21 with its axis parallel to the axisof the spindle 8. This shaft can be rotated by several well known meansas by a moving belt on the pulley 22. The said pulley being keyed Orotherwise fastened to the shaft 21. Fastened to the shaft 21 inside ofthe wheel base 2 and between the bushings 13 and 14 and also between thetwo sides of the bell crank 16 is a driving pulley 23 Fig. 8. An endlessbelt 24 operatively connects the driving pulley 23 and spindle pulley 10and passes in contact with the idler' pulleys 17 and 18 and thus causesthe rotation of the abrasive wheel 9 actuated primarily by the saidmoving belt on the pulley 22. Pivotally attached to the bell crank 16 isa counter weight 25 formed of several separate plates partly so as toadmit adjustment of the tension in the belt 24. This counter weight 25also through the bell crank 16, belt 24 and wheel slide 7 holds the nutI11 tightly and without play against the thread of the screw 12. Thethrust thus caused on the screw 12 is taken by a knife edge which willbe hereinafter fully explained.

Adjustably fastened to the reciprocating table 3 Fig. 6 in the slot 32by the screw 26 and nuts 27 is the dog 28. Threaded into the dog 28 Fig.3 is an adjustable knurled screw 29 having a knurled nut 30. The

oliice of this screw is to actuate the lever 31 Fig. 5 fastened to theshaft 32 by means of the pin 33. Similarly another dog Fig. 6 and Fig. 7is adjustably fastened in the slot 32 and has threaded into it a knurledscrew 35 having a knurled nut 36, this screw points in a directionopposite to the direction of the screw 29 and is located in the dog 34so that it can actuate the lever 37, Fig. 5. This lever is fastened tothe shaft 32 by means of a pin 33. Figs. 16 and 17 are detailed views ofthe levers and 33.

Fastened to the lower end of the shaft 32 by means of the pin 39 is afeed plate 4() shown in detail views by Figs. 12 and 13; this plate isslotted and has fitted therein a block 41 adapted to be adjusted by thescrew 42. The screw 4-2 taps into the block 41 and shoulders in thebearing 40 Fig. 5 of the feed plate 40 and has a knurled knob 42 pinnedto it by the pin 422 Fig. 5 by which the block 41 can be adjusted fromthe maximum throw to Zero. The block 41 has a cylindrical portion 41Fig. 12 forming a bearing for the connecting rod 43 and tapped into thisturned portion 41 is a screw 44 with a sufliciently large head toprevent the said rod 43 from dropping oil'. The feed plate 40 has an arm402 into which is riveted a stud 45 at the lower end of this stud ispivotally connected a spring 46 in t-ension Fig. 3; the other end ofthis spring is similarly fastened to a stud 47 fixed in the base 1.

Fastened to the feed plate 40 Fig. 5 and thus to the shaft 32 by the pin39 is a double armed lever 48 shown in detail by views Figs. 14 and 15;this lever is adapted to actuate the rod 49 through the stud 50 Fig. 3and this rod is limited in a reciprocating motion by the studs 51 and 52striking the base 1. The office of the rod 49 is to control themechanism that reverses the direction of the motion of the table 3, andby means of the said studs 51 and 52 and the double lever 48 theintermittent oscillatory motion of the shaft 32 is limited in bothdirections being preferably approximately one half of a turn. The shaft32 is j ournaled in a bracket 53 fastened to the base 1 by screws 54.The operation of this part of my grinding machine feeding mechanism isas follows; Fig'. 3 the table 3 upon which the dogs 2S and 34 haverespectively previously been adjusted by means of the said clampingscrews 26, and then the screws 29 and 35 respectively adjusted so thatthe work 55 which rotates preferably in the direction of the arrow Fig.9 will properly traverse the face of the wheel 9 which rotates in thedirection of the arrow Fig. 8. As the reciprocating table 3 moves in thedirection of the arrow Fig. 3 the rounded end of the screw 29 strikesthe end of the lever 31 and has carried it and the shaft 32 with themembers attached thereto into the position shown which is slightly morethan one half of their total motion and also so that the spring 46 hassufficiently passed the dead center, and so that the tensions of thesaid spring is ample to complete the total oscillation of the shaft 32and the members attached thereto. In this eXtreme position the end 48Fig. 3 and Fig. 14 of the lever 48 will come in contact with the stud 50and move the rod 49 until the stud 52 strikes the base 1. Similarly whenthe table 3 moves in the direction opposite to the arrow Fig. 3 therounded end of the screw 35 in the dog 34 strikes the lever 37 and bymeans of it and the spring 46 the end 482 of the double armed lever 48will come in contact with the stud 50 and move the rod 49 until the stud51 strikes the base 1 thus completing the oscillation of the shaft 32 inthis direction. It will be noticed that the first part of the action ofthe shaft 32 in either direction is always positive being actuatedrespectively by the dogs fastened to the reciprocating table 3 and thatthe latter part is always by the power of the tension spring 46. Thispositive motion of the connecting rod 43 actuates a ratchet wheel 57while the motion due to the spring 46 merely returns the ratchet pawl 60for a new grip on the ratchet wheel 57. It will further be noticed thatthe positive motion of the rod 43 is always in the same direction, andthat the spring motion is always in the opposite direction.

Fastened to the feed plate 4() is a scale 56 Figs. 5 and 13 graduatedand figured so that each graduation respectivelyindicates a total numberof table reciprocations necessary to complete one revolution of theratchet wheel 57 when the block 41 is adjusted to that particulargraduation by the screw 42; for instance, if the ratchet wheel 57contained 120 teeth and the feed plate had twelve graduations they wouldrespectively indicate 120, 60, 40 30, 20, 17, 15, 13, 12, 11, 10 and 9passes of the table 3 to complete one revolution of the ratchet wheel 57(17, 13, 11 and 9 are approximate). That is the pawl 60 could optionallybe made to take either 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, or 13teeth of the ratchet wheel 57 at each pass of the table 3. Theusefulness of this possibility will be hereinafter fully set forth.

The ratchet wheel 57 is keyed to the cam hand wheel 58 by the key 59Fig. 1 and the pawl 60 is pivoted on a stud 61 held by a plate 62 and acover plate 63; the plate 62 being sufficiently cut away to allow properaction of the pawl ratchet wheel and connecting rod as shown by dottedlines in Fig. 4. These plates 62 and 63 are fastened together by thescrews 64 and pins 65 and are adapted to oscillate one on a shoulder 58on the hub of the cam hand wheel 58, and the other on the shoulder 57 ofthe ratchet wheel 57, by means of the connecting rod 43 which ispivotally connected to the said plates through the stud 66; this stud 66is lhown in its preferred relation to stud 61 in Fastened to the insideof the cam hand wheel- 58 by means of the key 67 and screw 68 is a cam69; the cam surface 69 can be various shapes to suit the various kindsof work being ground. It is intended that the operator shall haveseveral cams on hand to select from. Fig. 11 is a development suggestingone form the cam surface 691 may take. Beginning at the point near thearrow the cam has a rapidly rising surface increasing by variableincrements until at the extreme left it terminates in a straight line.The cam surface 691 is adapted to actuate a roller 70 Fig. 1 with apreferably crowned periphery; this roller is supported by a stud 71fastened into one end of the lever 72; this lever 72 which is shown bydetail views Fig. 24 and Fig. 25 is slotted and straddles the screw 12with sufficient clearance to perform its function without touching thescrew; into portions of the lever 72 is threaded a ring 73 having aSpanner hole 731 and having the inner sur* face 7 32 adapted for a knifeedge bearing. The slotted end of the lever 72 has grooves 7 22 Fig. 24adapted to receive the knife 'edge 74 shown by detail views Figs. 26 and27; this knife edge is held in position on the lever 72 by pins 74'; thesides 72 of the lever 72 are adjustably fitted in the cam block 75 shownin detail views Figs. 18 and 19; this block is fastened to the base 1 bythe screws 76. Adjustably mounted in the cam block 75 is a slide 77adapted to straddle the lever 72 and screw 12; this slide has mounted onit two knife edges 78 shown by detail views Figs. 22 and 23; these aretongued into the slide 77 and also pinned thereto by the pins 781; theslide is adjusted by means of the screw 79 and graduated knob 80, thescrew 79 being shouldered in the cam block 75. On the screw 12 is ashoulder collar 121 and against this is located without play a splitwasher and knife edge bearing 81 shown also by detail views Figs. 28 and29.

The operation is as follows: The screw 12 has a continual pull due tothe counterweight 25 Fig. 8, thus forcing the knife edge bearing 81against the knife edge 74 mounted on the lever 72, and this lever inturn through the ring 73 which is threaded into it forces the surface732 of the said ring against the two knife edges 78 fastened on theslide 77, thus forcing the roller 70 against the cam surface 691 of thecam 69. Now assuming that the cam surface 691 approximates the developedsurface shown in Fig. 11, then by turning the cam hand wheel 58 in thedirection that the hands of a clock revolve, the said cam surface willcause the lever 72 to move the screw 12 and hence the wheel slide 7 andwheel 9 toward the axis of the work 55. 1f the total throw of the cam 68is .18 of an inch and the adjustment of the slide 77 by means of thescrew 79 is suficient to allow the relation of the distance from thebearing point of the roll to the bearing edge of the knife edge 78 andthe distance of the bearing of the knife edge 78 to the bearing of theknife edge 74 to be respectively as 3 to 1 as a maximum or 3 to 0 as aminimum, then the maximum throw of the screw will be one third of .18 or.06 of an inch, then if the threads of the adjusting screw 79 are 20 perinch, and the number of graduations on the knob 80 are 60 then onegraduation would indicate of an inch movement of the screw 12 or .0001of an inch change in the diameter of the work, and one turn of the knob80 would indicate .006 of an inch change in the diameter of the work 55,and 20 turns would give the maximum or .12 of an inch variation.

The abrupt portion 692 of the cam 69 Fig. 11 is intended to allow thewheel slide 7 and wheel 9 to move suiiiciently far back from the axis ofthe Work 55 to allow the easy removal of the same and the inserting ofanother piece; when this new piece of work is in place on the centers 51and 61 of the grinding machine and the machine has 'been started it isnot necessary for the operator to wait until the wheel 9 due to theaction of the cam 69 reaches the work 55, he can turn the cam hand wheel58 in the proper direction by hand until the emery wheel 9 startsgrinding and then allow it to continue automatically until it knocks ofor stops itself, by means of the above said abrupt portion 692 of thesurface of the cam 69 Fig. 11, which allows the counterweight 25 to pullthe wheel 9 away from the work 55, because of the roll 70 dropping overthe aforesaid abrupt portion 692 of the cam 69.

The hand wheel 82 is fastened to the screw 12 by the key 821 and hasrotatively mounted on its hub 822 a disk 83, this disk can be clamp-edto the said hub by means of the knurled screw 84 threaded into the endof screw 12, the point of which 8411 engages one end of a conicallypointed pin 85 and is adapted to force the other end of the said pininto one side of the annular groove 831 in the disk 83 and thus clampthe disk 83 and hold it firmly against the surface 823 of the hand wheel82. Vhen it is desired to adjust the disk 83 the knurled screw 84 isslightly unserewed. 1f the screw 12 is right handed and threaded intothe half nut 11 and has 5 threads per one inch, so that one turn of thehand wheel moves the wheel slide 7 and wheel 9, .2 of an inch and if thedisk 83 on its periphery is graduated into 400 divisions then onedivision would indicate of an inch movement of the abrasive wheel 9 or.001 of an inch in the diameter of the work 55.

Fastened to the plate 62 by a screw 86 is a plate 861 Fig. 3 having anindex line thereon by which the amount of adjustment of the disk 83 canbe ascertained. The hand Wheel 82 and disk 83 are used to adjust thewheel 9 relative to the work 55. r1`he cam mechanism hereinbeforedescribed will always knock off or stop grinding the work as soon as thesaid wheel 9 has reached a. limit fixed by the cam 69; now that limitcan be changed as hereinbefore explained by turning the knob 80. 1t canalso be changed a fraction of one thousandth of an inch or more byturning the hand wheel 82. By making note of the particular graduationthe emery wheel 9 can be easily returned to the same point aftergrinding a number of other sizes or shoulders on the same or differentpieces of work, for instance if another diameter on the work is .200 ofan inch larger or smaller, one turn of the hand wheel in the properdirection will properly locate the wheel 9 for grinding the saidshoulder. That is any number of diameters can readily be reproduced byreturning the hand wheel 82 and disk 83 to their proper graduated point.Any change due to the wear of the abrasive wheel can when necessary becorrected by the fine adjustment provided by the screw 79 and knob 80 ashereinbefore described.

Having described my new grinding ma* chine feeding mechanism 1 will nowgive a general description of the operation.

The abrasive wheel 9 being of the proper grade and revolving at thecorrect speed in the direction of the arrow Fig. 8 and the work 55 orpiece to be ground being snugly located on the centers 51 and 61, androtated thereon by means in the head 5 in the direction of the arrowFig. 9, and the table 3 reciprocating through a proper distance in thetracks 31 determined by the dogs 28 and 31 Fig. 7, the operator knowingthe approximate amount of material to be received from the workoptionally turns the knob 80 on the screw 79 and moves the knife edges78 until the graduation on the cam block Fig. 19 indicates a maximumtotal longitudinal movement of the screw 12, as for instance .04 of aninch. Then the operator optionally determines about the number of passesor reciprocations the work must make. That is if the work is to bereduced in diameter .08 of an inch that is .O4 of an inch on a side, andthe feed of the wheel 9 toward the axis of the work 55 is to be actuatedby a cam feeding by constant increments, the feeding taking place ateach end of the work when the respective dog actuates the feedingmechanism, then if the block il is set at the graduation for ten passeson the scale 56 each pass of the Wheel will remove .004 of an inch ofmaterial from the work 55 and after ten passes the cam 69 will have madeabout one revolution and the abrasive wheel 9 and slide 7 will havemoved back from the work 5 5 and the work can then be removed and a newpiece inserted.

In the above case if the b-lock 4l had been set for twenty passes then.002 of an inch of material would have been removed at each passproviding that the cam face 691 was shaped to give constant incrementsof feed. But if the operator has used a cam with a surface approximatelythat. shown by G91 Fig. 1l then the feeding increments would vary. Therst increments being greater than the last for the purposes set forthand obviously the work would be done much more quickly and with a betterfinish than with the constant feed cam, but for facing a shoulder theconstant increment feed would perhaps be best. After the grindingmachine has automatically ground one piece exactly to the requireddimensions, it will duplicate any number of pieces the only ele* ment ofchange being the wear of the grinding surface of the wheel 9, this isknown to be very little ordinarily and the error in the work can whennecessary be corrected by turning the knob 80.

Work having a number of diameters can easily be duplicated ashereinbefore explained by noting the respective graduation on the disk83.

I claim:

l. The combination of a stroke-regulating means for finishing the work;a cam for regulating amount of stock to be removed; means for graduallyreducing the amount of feed; means for stopping the feed at apredetermined point and making a number of traverses of the work pastthe wheel without feeding; means for compensating for wear of the wheel;means for grinding different diameters of work with the same initialadjustment; and means for measuring differences in the diameter of theWork.

2. In a grinding machine, the combination of stroke-regulating means forfinishing the work with means for regulating the amount of stock to beremoved and including a movable cam.

3. In a grinding machine, the combination of a cam for graduallyreducing the amount of feed with means for stopping the feed at apredetermined pointand making a number of traverses of the work past theWheel without feeding.

t. The combination of means for stopping the feed at a predeterminedpoint; means for making a number of traverses of work past the wheelwithout feeding; and means for compensating for the wear of the wheel,said means for stopping the feed at a predetermined point including acam feed mechanism and also a cam limiting the movement of the grindingmechanism.

5. In a grinding machine feeding mechanism, the combination of a leverwith a fixed knife edge adapted to engage a wheel support; a wheelsupport; a roller adapted to be actuated by a cam; a cam; a fulcrumplate adapted to co-act with the knife edge to form the fulcrum for saidlever, the said fulcrum knife edge being adjustable relatively to saidfixed knife edge.

6. The combination in a grinding machine of a feeding mechanism; abracket for supporting the feed works; a reciprocating table, andmechanism for actuating the feed through a feed-rod by means of areciprocating table.

In testimony whereof I afiix my signature in the presence of twowitnesses.

CONRAD M. CONRADSON.

Witnesses:

FREDERICK D. STANTON, ALBERT E. MoIR.

